66995554 has 4 divisors (see below), whose sum is σ = 100493334. Its totient is φ = 33497776.

The previous prime is 66995519. The next prime is 66995561. The reversal of 66995554 is 45559966.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 66667225 + 328329 = 8165^2 + 573^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 66995498 and 66995507.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16748887 + ... + 16748890.

Almost surely, 2^66995554 is an apocalyptic number.

66995554 is a deficient number, since it is larger than the sum of its proper divisors (33497780).

66995554 is a wasteful number, since it uses less digits than its factorization.

66995554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33497779.

The product of its digits is 1458000, while the sum is 49.

The square root of 66995554 is about 8185.0811846921. The cubic root of 66995554 is about 406.1458259439.

The spelling of 66995554 in words is "sixty-six million, nine hundred ninety-five thousand, five hundred fifty-four".